"Typing Insights"? - O&O has you covered:
Typing Insights is an opt-in feature that some people actually like, that corrects mistakes and auto-completes frequently typed words for you, based on a personal profile of your typing habits. But to make it work it has to collect data about your typing. While other similar 3rd party apps can manage to save this data locally and not phone home to hand it over to the developers to do with as they please, Microsoft needs to have this data in their control, on their servers, so that it will work with a single profile in the cloud, they say, that will be shared across all computers you log into with your Microsoft account. The profile is also shared with one of their Android speed typing apps.
You can easily turn the feature off, but they make it difficult to clear the typing data from your cloud stored profile, so if you log into another computer with your Microsoft account, it will go right back to suggesting stuff from your existing, cloud stored typing profile. If you want to clear that profile, you'll probably end up wasting more time than you'd care to, googling for how to do it and digging around in Windows for all the hidden settings. (I recently had to help someone do that, when the feature kept suggesting an old, compromised Yahoo account, whenever they were tying to log into their email, on any computer they used, at both work and home.)
But of course, once you do figure out how to clear it, that doesn't mean that Microsoft is going to be a sweetheart and completely delete all the data from their servers, and not keep and use a copy for their own purposes.
People that actually do like the feature aren't going to think about what may be happening behind the scenes, with their data, or possibly not care. And they certainly aren't going to want some 3rd party app like O&O to disable their much loved Windows feature. (my friend that had to clear their profile was upset that they lost their entire typing history and couldn't edit it to remove just the one thing they wanted removed)
Of course it's easy to avoid Typing Insights altogether (and a lot of other "features") by never logging into any computer, not even once, with a Microsoft account and not installing their app on your phone.
Then again, if you keep things in your Google account, your Outlook account or surf the web... they will surely find things out about you (even if you don't have a Facebook account).
As I said before:
Privacy is an illusion. It only exists in your mind, and only for as long as you can keep your thoughts in there and not let any bit of them escape.
It's still safe to sit motionless, calm and expressionless, and just think...for now. But once you do anything else, you are letting your thoughts escape your mind, into a world where you don't have much control over how they will be used by others.